Contouring is the process of identifying an object within an image by outlining or otherwise distinguishing the object from the rest of the image. Medical images, such as CT (computed tomography), MR (magnetic resonance), US (ultrasound), or PET (positron emission tomography) scans, are regularly contoured to identify certain pieces of anatomy within the image. For example, a radiologist or oncologist may contour a medical image to identify a tumor within the image. Software tools are available to assist in this type of “manual” contouring, in which the physician uses the software to create the contour by tracing the boundary of the object or objects within the image. In addition to manual contouring software, so-called automatic and semi-automatic contouring software products are also available. Automatic contouring software may be used to automatically detect an object or objects within an image and to automatically create a contour to identify the object(s) within the image. However, fully automated contouring software is not yet reliable for most medical imaging applications. Accordingly, semi-automatic contouring software is often used that automatically generates contours for an image based on at least some manually-created input, such as a previously contoured image of the same or similar anatomy.
In accordance with the teachings described herein, systems and methods are provided for generating a contour for a medical image. The system may include a contour synthesis engine that is configured to receive a plurality of contours for a medical image, the plurality of contours identifying at least one object within the medical image. The contour synthesis engine may be further configured to synthesize a combined contour from the plurality of contours by selecting portions of the plurality of contours based on one or more pre-defined contour combination criterion, the one or more pre-defined contour combination criterion including a designated number of contour overlaps such that any region where at least the designated number of contours are overlapping is included in the combined contour.
A processor-implemented method of generating a contour for a medical image may include the steps of receiving a plurality of contours that identify an object within the medical image, and synthesizing a combined contour from the plurality of contours by selecting portions of the plurality of contours based on one or more pre-defined contour combination criterion. In certain embodiments, the one or more pre-defined contour combination criterion may comprise a pre-defined number of overlapping contours such that any portion of the plurality of contours that includes at least the pre-defined number of overlapping contours is included in the combined contour. In addition, some embodiments may include the step of receiving a user input to modify the combined contour by adding an additional region or removing a region from the plurality of contours.